globle struct lhsParseNode *GetExpressionVarConstraints(
struct lhsParseNode *theExpression)
{
struct lhsParseNode *list1 = NULL, *list2;
for (; theExpression != NULL; theExpression = theExpression->bottom)
{
if (theExpression->right != NULL)
{
list2 = GetExpressionVarConstraints(theExpression->right);
list1 = AddToVariableConstraints(list2,list1);
}
if (theExpression->type == SF_VARIABLE)
{
list2 = GetLHSParseNode();
if (theExpression->referringNode != NULL)
{ list2->type = theExpression->referringNode->type; }
else
{ list2->type = SF_VARIABLE; }
list2->value = theExpression->value;
list2->derivedConstraints = TRUE;
list2->constraints = CopyConstraintRecord(theExpression->constraints);
list1 = AddToVariableConstraints(list2,list1);
}
}
return(list1);
}
globle struct lhsParseNode *DeriveVariableConstraints(
void *theEnv,
struct lhsParseNode *theNode)
{
struct lhsParseNode *orNode, *andNode;
struct lhsParseNode *list1, *list2, *list3 = NULL;
int first = TRUE;
/*===============================*/
/* Process the constraints for a */
/* single connected constraint. */
/*===============================*/
for (orNode = theNode->bottom; orNode != NULL; orNode = orNode->bottom)
{
/*=================================================*/
/* Intersect all of the &'ed constraints together. */
/*=================================================*/
list2 = NULL;
for (andNode = orNode; andNode != NULL; andNode = andNode->right)
{
if ((andNode->type == RETURN_VALUE_CONSTRAINT) ||
(andNode->type == PREDICATE_CONSTRAINT))
{
list1 = GetExpressionVarConstraints(theEnv,andNode->expression);
list2 = AddToVariableConstraints(theEnv,list2,list1);
}
}
if (first)
{
list3 = list2;
first = FALSE;
}
else
{ list3 = UnionVariableConstraints(theEnv,list3,list2); }
}
return(list3);
}
static int TestCEAnalysis(
void *theEnv,
struct lhsParseNode *patternPtr,
struct lhsParseNode *theExpression,
int secondary,
int *errorFlag,
struct nandFrame *theNandFrames)
{
struct lhsParseNode *rv, *theList, *tempList, *tempRight;
if (theExpression == NULL) return FALSE;
/*=====================================================*/
/* Verify that all variables were referenced properly. */
/*=====================================================*/
rv = CheckExpression(theEnv,theExpression,NULL,(int) patternPtr->whichCE,NULL,0);
/*====================================================================*/
/* Temporarily disconnect the right nodes. If this is a pattern node */
/* with an attached test CE, we only want to propagate to following */
/* patterns, not to nodes of this pattern which preceded the test CE. */
/*====================================================================*/
tempRight = patternPtr->right;
patternPtr->right = NULL;
/*=========================================================*/
/* Determine the type and value constraints implied by the */
/* expression and propagate these constraints to other */
/* variables in the LHS. For example, the expression */
/* (+ ?x 1) implies that ?x is a number. */
/*=========================================================*/
theList = GetExpressionVarConstraints(theEnv,theExpression);
for (tempList = theList; tempList != NULL; tempList = tempList->right)
{
if (PropagateVariableDriver(theEnv,patternPtr,patternPtr,NULL,SF_VARIABLE,
(SYMBOL_HN *) tempList->value,tempList,FALSE,TEST_CE))
{
ReturnLHSParseNodes(theEnv,theList);
patternPtr->right = tempRight;
return(TRUE);
}
}
ReturnLHSParseNodes(theEnv,theList);
/*============================*/
/* Reconnect the right nodes. */
/*============================*/
patternPtr->right = tempRight;
/*========================================================*/
/* If the variables in the expression were all referenced */
/* properly, then create the expression to use in the */
/* join network. */
/*========================================================*/
if (rv != NULL)
{ *errorFlag = TRUE; }
else if (secondary)
{ patternPtr->secondaryNetworkTest = CombineExpressions(theEnv,patternPtr->secondaryNetworkTest,GetvarReplace(theEnv,theExpression,FALSE,theNandFrames)); }
else
{ patternPtr->networkTest = CombineExpressions(theEnv,patternPtr->networkTest,GetvarReplace(theEnv,theExpression,FALSE,theNandFrames)); }
return FALSE;
}
